Improvement of payment on the internet as a development factor of digital economy in Serbia

The emergence of e-commerce has also brought new financial needs that in many cases could not meet the traditional payment system. On the other hand, apart from the need for new solutions, e-commerce technology has enabled the creation of new billing system or the improvement of existing payment mechanisms and systems. Also, we should not ignore the fact that efficient and secure payment basis for further expansion of electronic commerce, as revenue collection as well as in every store, it remains the core of a successful business in the digital environment. According to some estimates, the electronic payments via the internet or through other networks, increasing annually by about $ 75 billion

Elektronski registar robnih zapisa kao korak od papirnog ka elektronskom robnom zapisu

The aim of this paper is to determine the economic viability of the electronic warehouse receipt registry introduction, as a step toward electronic warehouse receipts. Both forms of warehouse receipt paper and electronic exist in practice, but paper warehouse receipts are more widespread. In this paper, the dematerialization process is analyzed in two steps. The first step is the dematerialization of warehouse receipt registry, with warehouse receipts still in paper form. The second step is the introduction of electronic warehouse receipts themselves. Dematerialization of warehouse receipts is more complex than that for financial securities, because of the individual characteristics of each warehouse receipt. As a consequence, electronic warehouse receipts are in place for only to a handful of commodities, namely cotton and a few grains. Nevertheless, the movement towards the electronic warehouse receipt, which began several decades ago with financial securities, is now taking hold in the agricultural sector. In this paper is analyzed Serbian electronic registry, since the Serbia is first country in EU with electronic warehouse receipts registry donated by FAO. Performed analysis shows the considerable impact of electronic warehouse receipts registry establishment on enhancing the security of the system of public warehouses, and on advancing the trade with warehouse receipt.Cilj ovog rada je da se utvrdi ekonomska opravdanost uvođenja elektronske evidencije robnog zapisa, kao koraka ka uvođenju u potpunosti elektronskog robnog zapisa. Obe forme robnog zapisa postoje u praksi, ali je papirni oblik robnog zapisa više u upotrebi. U ovom radu proces dematerijalizacije je analiziran u dva koraka. Prvi je dematerijalizacija knjige robnih zapisa, dok je robni zapis u papirnoj formi. Drugi korak je uvođenje potpunog sistema elektronskog robnog zapisa. Dematerijalizacija robnog zapisa je kompleksnija u odnosu na dematerilalizaciju efektnih hartija od vrednosti zbog individualnih karakteristika svakog robnog zapisa. Kao rezultat ovoga, elektronski sistemi robnih zapisa su retki u svetu i u primeni su za samo nekoliko vrsta roba, poput pamuka i nekoliko vrsta žitarica. Ipak promena od papirnih hartija od vrednosti ka elektronskim u finansijskom sektoru, koja je počela pre nekoliko decenija, sada se intenzivira i u oblasti poljoprivrednih proizvoda. Analize u ovom radu pokazuju značajan uticaj elektronske evidencije robnih zapisa na povećanje sigurnosti sistema javnih skladišta i unapređenje trgovanja robnim zapisima. PR Projekat Ministarstva nauke Republike Srbije, br.III 46006

Competitiveness of Serbia in the digital market

Internet is now considered as basic infrastructure of a country, in the same way as electricity, water or transport networks. In recent years it occupies a key economic role, so that the concept of the Internet economy is becoming a widely used term. Bearing in mind the growing importance of the Internet as a political tool, the question of the scope of the Internet economy is becoming very important. There is great interest in determining the scope of the internet economy as a way to understand the effects of different investment strategies, regulatory decisions and political decisions. Europe has been a leader in the development of digital ecosystems as a key factor that drives innovation and competitiveness. It is also the place where were developed some of the best connected and most innovative economies in the world. This paper deals with the current state and the readiness of Serbia to join the new economic trends directed by the development of information and communication technologies

The Impact of Recycled Concrete Aggregate on the Stiffness, Fatigue, and Low-Temperature Performance of Asphalt Mixtures for Road Construction

The need for road (re)construction materials is constantly growing. At the same time, there is a limited quantity of new, high-quality materials available and a buildup of secondary/recycled construction materials. One possible solution may be the use of recycled concrete aggregate (RCA) in asphalt mixtures instead of natural aggregate (NA), which also promotes economic and environmental sustainability. The potential use of fine and coarse RCA in road asphalt mixtures is analyzed in this work. Nine asphalt mixtures were tested for base course layers, where RCA was used as a NA substitute. The impact of the quantity of RCA (up to 45% by mass) on the resulting physical and mechanical properties of asphalt mixtures was investigated, and consequently compared with the properties of a reference control mixture produced with NA only. Results reveal that the addition of RCA requires higher bitumen in comparison to the control mixture (up to 1%). Consequently, mixtures with RCA had 15 20% lower stiffness and up to 26% higher critical fatigue strain value (epsilon(6)). Although RCA mixtures contained more bitumen, their low-temperature resistance was slightly inferior compared with the control mixture (failure temperatures were up to 4.3 degrees C higher). In conclusion, asphalt mixtures with up to 45% RCA can be used without substantially reducing performance

Influence of acid treatment and carbonation on the properties of recycled concrete aggregate

Recycled concrete aggregate (RCA), obtained by crushing of original (old) concrete, consists of natural aggregate grains and a cement mortar matrix. The presence of old adhered cement mortar, which has higher porosity than natural aggregate, causes unfavourable properties of RCA. The research conducted in order to improve the quality of RCA and to enable its greater application in the construction industry is presented in this paper. Therefore, RCA was subjected to quality improvement treatments with hydrochloric acid and carbon dioxide (accelerated carbonation). The first procedure was aimed at partially removing the adhered cement mortar and the second at reinforcing the cement matrix. The physical, mechanical and chemical properties of all three types of RCA were tested. After the pre-soaking acid treatment (0.1 mol/dm(3) HCl), RCA showed reduced water absorption (up to 3%); the process of accelerated carbonation also led to reduced water absorption (13-20%) as well as to improved mechanical properties (similar to 10%). A scanning electron microscopy investigation revealed that the carbonation process, as expected, significantly reduces porosity of RCA. The overall results show that if RCA is obtained by crushing of compact, high-quality concrete, the procedures of aggregate quality improvement are not necessary

The Impact of Recycled Concrete Aggregate on the Stiffness, Fatigue, and Low-Temperature Performance of Asphalt Mixtures for Road Construction

The need for road (re)construction materials is constantly growing. At the same time, there is a limited quantity of new, high-quality materials available and a buildup of secondary/recycled construction materials. One possible solution may be the use of recycled concrete aggregate (RCA) in asphalt mixtures instead of natural aggregate (NA), which also promotes economic and environmental sustainability. The potential use of fine and coarse RCA in road asphalt mixtures is analyzed in this work. Nine asphalt mixtures were tested for base course layers, where RCA was used as a NA substitute. The impact of the quantity of RCA (up to 45% by mass) on the resulting physical and mechanical properties of asphalt mixtures was investigated, and consequently compared with the properties of a reference control mixture produced with NA only. Results reveal that the addition of RCA requires higher bitumen in comparison to the control mixture (up to 1%). Consequently, mixtures with RCA had 15-20% lower stiffness and up to 26% higher critical fatigue strain value (E6). Although RCA mixtures contained more bitumen, their low-temperature resistance was slightly inferior compared with the control mixture (failure temperatures were up to 4.3 C higher). In conclusion, asphalt mixtures with up to 45% RCA can be used without substantially reducing performance

Statistička analiza rezultata ispitivanja fizičko-mehaničkih svojstava kontrolnih betonskih kocki

Cilj ovog istraživanja je prikupljanje, obrada i statistička analiza rezultata ispitivanja uzoraka betonskih kocki koji su ispitani u Laboratoriji za materijale Građevinskog fakulteta u Beogradu prema standardu SRPS ISO 4012:2000 u periodu od 2012. do 2017. godine. Za potrebe analize, preuzeti su podaci iz Izveštaja o ispitivanju kontrolnih betonskih kocki, prepoznate su i klasifikovane osnovne karakteristike očvrslog betona. Izvršena je statistička analiza datuma betoniranja, starosti uzoraka, sastava betona, zapreminske mase, čvrstoće pri pritisku, zahtevane marke betona itd. Statistika je pokazala da su najčešće upotrebljavani cementi sledećih oznaka: CEM II A-M (V-L), CEM II A-M (S-L), CEM II A-S, a da najveće učešće imaju marke betona MB 30 sa 66,8% i MB 40 sa 14,3% udela

Национална економија

Serbian. У овом одељку разматрају се опште карактеристике националне економије. У првом делу приказан је њен историјски развој, који је обухватио привреду у средњовековној српској држави Немањића, преко развоја у оквирима турске феудалне државе, изградње самосталне српске државе након српских устанака и ослобођења од Турске, па до развоја у савременим условима 20. и 21. века. Тај вишевековни развој протицао је у сталним напорима да се превазиђе наслеђена економска заосталост, да се унапреди и модернизује привреда, односно да се претежно аграрна земља претвори у земљу с модерном индустријском привредом, али и уз отпоре изражене у супротној тенденцији да се одржи аграрни, односно сељачки карактер земље. Ипак, био је то процес који се уз мање или више осцилација, али у целини успешно одвијао све до пред крај 20. века. Међутим, почев од последње деценије претходног века земља је током процеса транзиције била деиндустријализована, тако да је сада на нивоу развоја од пре неколико деценија, и стоји пред поновним захтевима за (ре)индустријализацијом. У другом делу разматрају се актуелне карактеристике привреде Србије, подељене у четири сектора. English. In this chapter the main characteristics of the national economy will be considered. In the first part there is explored its historical development. It involves the economy of the middle century Nemanjićs’ Serbian state, through the development in the framework of Turkish feudal state, the building of independent Serbian state after the Serbian uprisings and liberation from Turkey, up to development in modern circumstances of 20th and 21st centuries. This many centuries development characterize constant efforts to overcome the inherited economic backwardness, to move up and modernize the economy, i.e. to transform the predominantly agrarian state to the state with modern manufacturing economy, but also with resistances represented in opposite tendency to keep agrarian, i.e. peasant character of the state. Although, it was the process, that successfully carried out until to last decade of 20th century. But, since this decade the state was deindustrialized through the transition process, so it is now on the level of some decade before, and state is confronted with the repeated need for reindustrialization. In the second part of this chapter the actual characteristics of the Serbian economy are considered, divided in four sectors

Self-employment and enterpreneurship as a choice: An example of Serbia

The transition to a market economy in Serbia still hasn’t created a good enough environment for enterpreneurship to flourish. Enterpreneurship is more commonly manifested as a result of the push effect- the need for work and survival, and it’s success is the result of the pull effect- recognizing business possibilities and market chances. The economic crisis has further increased unwanted demographic movements, especially inside migration of younger and more educated population from rural areas to bigger cities. The only way to battle the high unemployment rate of women and the young in Serbia is to create more attractive conditions for the development of enterpreneurship. That can be acomplished by bettering the macroeconomic ambience of business as well as by funding the need for start-up capital. The first priority is to create the conditions necessary for safe and long term business development. [Projekat Ministarstva nauke Republike Srbije, br. 47007/III

Influence of acid treatment and carbonation on the properties of recycled concrete aggregate

Recycled concrete aggregate (RCA), obtained by crushing of original (old) concrete, consists of natural aggregate grains and a cement mortar matrix. The presence of old adhered cement mortar, which has higher porosity than natural aggregate, causes unfavourable properties of RCA. The research conducted in order to improve the quality of RCA and to enable its greater application in the construction industry is presented in this paper. Therefore, RCA was subjected to quality improvement treatments with hydrochloric acid and carbon dioxide (accelerated carbonation). The first procedure was aimed at partially removing the adhered cement mortar and the second at reinforcing the cement matrix. The physical, mechanical and chemical properties of all three types of RCA were tested. After the pre-soaking acid treatment (0.1 mol/dm3 HCl), RCA showed reduced water absorption (up to 3%); the process of accelerated carbonation also led to reduced water absorption (13–20%) as well as to improved mechanical properties (∼10%). A scanning electron microscopy investigation revealed that the carbonation process, as expected, significantly reduces porosity of RCA. The overall results show that if RCA is obtained by crushing of compact, high- -quality concrete, the procedures of aggregate quality improvement are not necessary